summaryrefslogtreecommitdiffstats
path: root/arch/mips/jazz/jazzdma.c
blob: e8e0ffb9354d2295a0ea9cb5939e4fb05fb3efae (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
/*
 * Mips Jazz DMA controller support
 * Copyright (C) 1995, 1996 by Andreas Busse
 *
 * NOTE: Some of the argument checking could be removed when
 * things have settled down. Also, instead of returning 0xffffffff
 * on failure of vdma_alloc() one could leave page #0 unused
 * and return the more usual NULL pointer as logical address.
 */
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/mm.h>
#include <linux/bootmem.h>
#include <linux/spinlock.h>
#include <asm/mipsregs.h>
#include <asm/jazz.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <asm/dma.h>
#include <asm/jazzdma.h>
#include <asm/pgtable.h>

/*
 * Set this to one to enable additional vdma debug code.
 */
#define CONF_DEBUG_VDMA 0

static unsigned long vdma_pagetable_start;

static DEFINE_SPINLOCK(vdma_lock);

/*
 * Debug stuff
 */
#define vdma_debug     ((CONF_DEBUG_VDMA) ? debuglvl : 0)

static int debuglvl = 3;

/*
 * Initialize the pagetable with a one-to-one mapping of
 * the first 16 Mbytes of main memory and declare all
 * entries to be unused. Using this method will at least
 * allow some early device driver operations to work.
 */
static inline void vdma_pgtbl_init(void)
{
	VDMA_PGTBL_ENTRY *pgtbl = (VDMA_PGTBL_ENTRY *) vdma_pagetable_start;
	unsigned long paddr = 0;
	int i;

	for (i = 0; i < VDMA_PGTBL_ENTRIES; i++) {
		pgtbl[i].frame = paddr;
		pgtbl[i].owner = VDMA_PAGE_EMPTY;
		paddr += VDMA_PAGESIZE;
	}
}

/*
 * Initialize the Jazz R4030 dma controller
 */
void __init vdma_init(void)
{
	/*
	 * Allocate 32k of memory for DMA page tables.  This needs to be page
	 * aligned and should be uncached to avoid cache flushing after every
	 * update.
	 */
	vdma_pagetable_start =
		(unsigned long) alloc_bootmem_low_pages(VDMA_PGTBL_SIZE);
	if (!vdma_pagetable_start)
		BUG();
	dma_cache_wback_inv(vdma_pagetable_start, VDMA_PGTBL_SIZE);
	vdma_pagetable_start = KSEG1ADDR(vdma_pagetable_start);

	/*
	 * Clear the R4030 translation table
	 */
	vdma_pgtbl_init();

	r4030_write_reg32(JAZZ_R4030_TRSTBL_BASE,
			  CPHYSADDR(vdma_pagetable_start));
	r4030_write_reg32(JAZZ_R4030_TRSTBL_LIM, VDMA_PGTBL_SIZE);
	r4030_write_reg32(JAZZ_R4030_TRSTBL_INV, 0);

	printk("VDMA: R4030 DMA pagetables initialized.\n");
}

/*
 * Allocate DMA pagetables using a simple first-fit algorithm
 */
unsigned long vdma_alloc(unsigned long paddr, unsigned long size)
{
	VDMA_PGTBL_ENTRY *entry = (VDMA_PGTBL_ENTRY *) vdma_pagetable_start;
	int first, last, pages, frame, i;
	unsigned long laddr, flags;

	/* check arguments */

	if (paddr > 0x1fffffff) {
		if (vdma_debug)
			printk("vdma_alloc: Invalid physical address: %08lx\n",
			       paddr);
		return VDMA_ERROR;	/* invalid physical address */
	}
	if (size > 0x400000 || size == 0) {
		if (vdma_debug)
			printk("vdma_alloc: Invalid size: %08lx\n", size);
		return VDMA_ERROR;	/* invalid physical address */
	}

	spin_lock_irqsave(&vdma_lock, flags);
	/*
	 * Find free chunk
	 */
	pages = (size + 4095) >> 12;	/* no. of pages to allocate */
	first = 0;
	while (1) {
		while (entry[first].owner != VDMA_PAGE_EMPTY &&
		       first < VDMA_PGTBL_ENTRIES) first++;
		if (first + pages > VDMA_PGTBL_ENTRIES) {	/* nothing free */
			spin_unlock_irqrestore(&vdma_lock, flags);
			return VDMA_ERROR;
		}

		last = first + 1;
		while (entry[last].owner == VDMA_PAGE_EMPTY
		       && last - first < pages)
			last++;

		if (last - first == pages)
			break;	/* found */
	}

	/*
	 * Mark pages as allocated
	 */
	laddr = (first << 12) + (paddr & (VDMA_PAGESIZE - 1));
	frame = paddr & ~(VDMA_PAGESIZE - 1);

	for (i = first; i < last; i++) {
		entry[i].frame = frame;
		entry[i].owner = laddr;
		frame += VDMA_PAGESIZE;
	}

	/*
	 * Update translation table and return logical start address
	 */
	r4030_write_reg32(JAZZ_R4030_TRSTBL_INV, 0);

	if (vdma_debug > 1)
		printk("vdma_alloc: Allocated %d pages starting from %08lx\n",
		     pages, laddr);

	if (vdma_debug > 2) {
		printk("LADDR: ");
		for (i = first; i < last; i++)
			printk("%08x ", i << 12);
		printk("\nPADDR: ");
		for (i = first; i < last; i++)
			printk("%08x ", entry[i].frame);
		printk("\nOWNER: ");
		for (i = first; i < last; i++)
			printk("%08x ", entry[i].owner);
		printk("\n");
	}

	spin_unlock_irqrestore(&vdma_lock, flags);

	return laddr;
}

EXPORT_SYMBOL(vdma_alloc);

/*
 * Free previously allocated dma translation pages
 * Note that this does NOT change the translation table,
 * it just marks the free'd pages as unused!
 */
int vdma_free(unsigned long laddr)
{
	VDMA_PGTBL_ENTRY *pgtbl = (VDMA_PGTBL_ENTRY *) vdma_pagetable_start;
	int i;

	i = laddr >> 12;

	if (pgtbl[i].owner != laddr) {
		printk
		    ("vdma_free: trying to free other's dma pages, laddr=%8lx\n",
		     laddr);
		return -1;
	}

	while (pgtbl[i].owner == laddr && i < VDMA_PGTBL_ENTRIES) {
		pgtbl[i].owner = VDMA_PAGE_EMPTY;
		i++;
	}

	if (vdma_debug > 1)
		printk("vdma_free: freed %ld pages starting from %08lx\n",
		       i - (laddr >> 12), laddr);

	return 0;
}

EXPORT_SYMBOL(vdma_free);

/*
 * Map certain page(s) to another physical address.
 * Caller must have allocated the page(s) before.
 */
int vdma_remap(unsigned long laddr, unsigned long paddr, unsigned long size)
{
	VDMA_PGTBL_ENTRY *pgtbl =
	    (VDMA_PGTBL_ENTRY *) vdma_pagetable_start;
	int first, pages, npages;

	if (laddr > 0xffffff) {
		if (vdma_debug)
			printk
			    ("vdma_map: Invalid logical address: %08lx\n",
			     laddr);
		return -EINVAL;	/* invalid logical address */
	}
	if (paddr > 0x1fffffff) {
		if (vdma_debug)
			printk
			    ("vdma_map: Invalid physical address: %08lx\n",
			     paddr);
		return -EINVAL;	/* invalid physical address */
	}

	npages = pages =
	    (((paddr & (VDMA_PAGESIZE - 1)) + size) >> 12) + 1;
	first = laddr >> 12;
	if (vdma_debug)
		printk("vdma_remap: first=%x, pages=%x\n", first, pages);
	if (first + pages > VDMA_PGTBL_ENTRIES) {
		if (vdma_debug)
			printk("vdma_alloc: Invalid size: %08lx\n", size);
		return -EINVAL;
	}

	paddr &= ~(VDMA_PAGESIZE - 1);
	while (pages > 0 && first < VDMA_PGTBL_ENTRIES) {
		if (pgtbl[first].owner != laddr) {
			if (vdma_debug)
				printk("Trying to remap other's pages.\n");
			return -EPERM;	/* not owner */
		}
		pgtbl[first].frame = paddr;
		paddr += VDMA_PAGESIZE;
		first++;
		pages--;
	}

	/*
	 * Update translation table
	 */
	r4030_write_reg32(JAZZ_R4030_TRSTBL_INV, 0);

	if (vdma_debug > 2) {
		int i;
		pages = (((paddr & (VDMA_PAGESIZE - 1)) + size) >> 12) + 1;
		first = laddr >> 12;
		printk("LADDR: ");
		for (i = first; i < first + pages; i++)
			printk("%08x ", i << 12);
		printk("\nPADDR: ");
		for (i = first; i < first + pages; i++)
			printk("%08x ", pgtbl[i].frame);
		printk("\nOWNER: ");
		for (i = first; i < first + pages; i++)
			printk("%08x ", pgtbl[i].owner);
		printk("\n");
	}

	return 0;
}

/*
 * Translate a physical address to a logical address.
 * This will return the logical address of the first
 * match.
 */
unsigned long vdma_phys2log(unsigned long paddr)
{
	int i;
	int frame;
	VDMA_PGTBL_ENTRY *pgtbl =
	    (VDMA_PGTBL_ENTRY *) vdma_pagetable_start;

	frame = paddr & ~(VDMA_PAGESIZE - 1);

	for (i = 0; i < VDMA_PGTBL_ENTRIES; i++) {
		if (pgtbl[i].frame == frame)
			break;
	}

	if (i == VDMA_PGTBL_ENTRIES)
		return ~0UL;

	return (i << 12) + (paddr & (VDMA_PAGESIZE - 1));
}

EXPORT_SYMBOL(vdma_phys2log);

/*
 * Translate a logical DMA address to a physical address
 */
unsigned long vdma_log2phys(unsigned long laddr)
{
	VDMA_PGTBL_ENTRY *pgtbl =
	    (VDMA_PGTBL_ENTRY *) vdma_pagetable_start;

	return pgtbl[laddr >> 12].frame + (laddr & (VDMA_PAGESIZE - 1));
}

EXPORT_SYMBOL(vdma_log2phys);

/*
 * Print DMA statistics
 */
void vdma_stats(void)
{
	int i;

	printk("vdma_stats: CONFIG: %08x\n",
	       r4030_read_reg32(JAZZ_R4030_CONFIG));
	printk("R4030 translation table base: %08x\n",
	       r4030_read_reg32(JAZZ_R4030_TRSTBL_BASE));
	printk("R4030 translation table limit: %08x\n",
	       r4030_read_reg32(JAZZ_R4030_TRSTBL_LIM));
	printk("vdma_stats: INV_ADDR: %08x\n",
	       r4030_read_reg32(JAZZ_R4030_INV_ADDR));
	printk("vdma_stats: R_FAIL_ADDR: %08x\n",
	       r4030_read_reg32(JAZZ_R4030_R_FAIL_ADDR));
	printk("vdma_stats: M_FAIL_ADDR: %08x\n",
	       r4030_read_reg32(JAZZ_R4030_M_FAIL_ADDR));
	printk("vdma_stats: IRQ_SOURCE: %08x\n",
	       r4030_read_reg32(JAZZ_R4030_IRQ_SOURCE));
	printk("vdma_stats: I386_ERROR: %08x\n",
	       r4030_read_reg32(JAZZ_R4030_I386_ERROR));
	printk("vdma_chnl_modes:   ");
	for (i = 0; i < 8; i++)
		printk("%04x ",
		       (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_MODE +
						   (i << 5)));
	printk("\n");
	printk("vdma_chnl_enables: ");
	for (i = 0; i < 8; i++)
		printk("%04x ",
		       (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
						   (i << 5)));
	printk("\n");
}

/*
 * DMA transfer functions
 */

/*
 * Enable a DMA channel. Also clear any error conditions.
 */
void vdma_enable(int channel)
{
	int status;

	if (vdma_debug)
		printk("vdma_enable: channel %d\n", channel);

	/*
	 * Check error conditions first
	 */
	status = r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5));
	if (status & 0x400)
		printk("VDMA: Channel %d: Address error!\n", channel);
	if (status & 0x200)
		printk("VDMA: Channel %d: Memory error!\n", channel);

	/*
	 * Clear all interrupt flags
	 */
	r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
			  r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
					   (channel << 5)) | R4030_TC_INTR
			  | R4030_MEM_INTR | R4030_ADDR_INTR);

	/*
	 * Enable the desired channel
	 */
	r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
			  r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
					   (channel << 5)) |
			  R4030_CHNL_ENABLE);
}

EXPORT_SYMBOL(vdma_enable);

/*
 * Disable a DMA channel
 */
void vdma_disable(int channel)
{
	if (vdma_debug) {
		int status =
		    r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
				     (channel << 5));

		printk("vdma_disable: channel %d\n", channel);
		printk("VDMA: channel %d status: %04x (%s) mode: "
		       "%02x addr: %06x count: %06x\n",
		       channel, status,
		       ((status & 0x600) ? "ERROR" : "OK"),
		       (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_MODE +
						   (channel << 5)),
		       (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_ADDR +
						   (channel << 5)),
		       (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_COUNT +
						   (channel << 5)));
	}

	r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
			  r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
					   (channel << 5)) &
			  ~R4030_CHNL_ENABLE);

	/*
	 * After disabling a DMA channel a remote bus register should be
	 * read to ensure that the current DMA acknowledge cycle is completed.
	 */
	*((volatile unsigned int *) JAZZ_DUMMY_DEVICE);
}

EXPORT_SYMBOL(vdma_disable);

/*
 * Set DMA mode. This function accepts the mode values used
 * to set a PC-style DMA controller. For the SCSI and FDC
 * channels, we also set the default modes each time we're
 * called.
 * NOTE: The FAST and BURST dma modes are supported by the
 * R4030 Rev. 2 and PICA chipsets only. I leave them disabled
 * for now.
 */
void vdma_set_mode(int channel, int mode)
{
	if (vdma_debug)
		printk("vdma_set_mode: channel %d, mode 0x%x\n", channel,
		       mode);

	switch (channel) {
	case JAZZ_SCSI_DMA:	/* scsi */
		r4030_write_reg32(JAZZ_R4030_CHNL_MODE + (channel << 5),
/*			  R4030_MODE_FAST | */
/*			  R4030_MODE_BURST | */
				  R4030_MODE_INTR_EN |
				  R4030_MODE_WIDTH_16 |
				  R4030_MODE_ATIME_80);
		break;

	case JAZZ_FLOPPY_DMA:	/* floppy */
		r4030_write_reg32(JAZZ_R4030_CHNL_MODE + (channel << 5),
/*			  R4030_MODE_FAST | */
/*			  R4030_MODE_BURST | */
				  R4030_MODE_INTR_EN |
				  R4030_MODE_WIDTH_8 |
				  R4030_MODE_ATIME_120);
		break;

	case JAZZ_AUDIOL_DMA:
	case JAZZ_AUDIOR_DMA:
		printk("VDMA: Audio DMA not supported yet.\n");
		break;

	default:
		printk
		    ("VDMA: vdma_set_mode() called with unsupported channel %d!\n",
		     channel);
	}

	switch (mode) {
	case DMA_MODE_READ:
		r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
				  r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
						   (channel << 5)) &
				  ~R4030_CHNL_WRITE);
		break;

	case DMA_MODE_WRITE:
		r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
				  r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
						   (channel << 5)) |
				  R4030_CHNL_WRITE);
		break;

	default:
		printk
		    ("VDMA: vdma_set_mode() called with unknown dma mode 0x%x\n",
		     mode);
	}
}

EXPORT_SYMBOL(vdma_set_mode);

/*
 * Set Transfer Address
 */
void vdma_set_addr(int channel, long addr)
{
	if (vdma_debug)
		printk("vdma_set_addr: channel %d, addr %lx\n", channel,
		       addr);

	r4030_write_reg32(JAZZ_R4030_CHNL_ADDR + (channel << 5), addr);
}

EXPORT_SYMBOL(vdma_set_addr);

/*
 * Set Transfer Count
 */
void vdma_set_count(int channel, int count)
{
	if (vdma_debug)
		printk("vdma_set_count: channel %d, count %08x\n", channel,
		       (unsigned) count);

	r4030_write_reg32(JAZZ_R4030_CHNL_COUNT + (channel << 5), count);
}

EXPORT_SYMBOL(vdma_set_count);

/*
 * Get Residual
 */
int vdma_get_residue(int channel)
{
	int residual;

	residual = r4030_read_reg32(JAZZ_R4030_CHNL_COUNT + (channel << 5));

	if (vdma_debug)
		printk("vdma_get_residual: channel %d: residual=%d\n",
		       channel, residual);

	return residual;
}

/*
 * Get DMA channel enable register
 */
int vdma_get_enable(int channel)
{
	int enable;

	enable = r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5));

	if (vdma_debug)
		printk("vdma_get_enable: channel %d: enable=%d\n", channel,
		       enable);

	return enable;
}